From the very beginning of the article on Wikipedia:

"Wind chill or windchill (popularly wind chill factor) is the lowering of body temperature due to the passing-flow of lower-temperature air.

It's a non-scientific term with no agreed exact formula and has nothing to do with inanimate objects.

Edit: Of course wind cools things - didn't mean to be nit-picking, I just don't like "windchill" because it's poorly defined. I mean there could be moisture on inanimate objects, that could be removed by dry air and cool further.. but there are good terms for those phenomenon such as evaporative cooling, convective, etc.